Saturday, November 12, 2011

Accurate length measurement for Lolong

Last Thursday 10 November 2011 at the request of National Geographic and with the consent of local officials I had the opportunity to measure Lolong, potentially the world's largest crocodile. Several news articles are misreporting the correct measurement, so I thought you'd like to hear the correct figure directly from me. I'll post a more detailed report when I'm able to do so, hopefully together with some impressive photos.

Lolong's total length was 6.17 metres, which is 20 feet 3 inches (20.25 feet). As a pure-bred saltwater crocodile, this certainly makes him the largest living crocodile in captivity. This is not an official Guinness record yet, there is a procedure that we have to go through before they can make a final decision, but we have all the required evidence for it. It will be several months before a decision is final.

Sorry Cassius!

I can also report that Lolong is in very good health, and is without doubt the most beautifully impressive crocodile I've ever seen.

I'm glad to hear Lolong is indeed over 20 feet in length! :) I suspected he would have been just slighly below 21 feet, but would that really matter that much? He belongs to the three biggest crocodiles that were ever reliably measured. Interesting is that they all are around 6.2 metres. It seems that this is about the normal maximum length they could reach, at least in the wild.

Dr Britton, I have a few questions.

1. Is it true that Lolong is around 50 years old? Let's say he lives for another 30 years. How much do you think he could still grow, could he grow to 21 or even 22 feet?

2. Rom Whitaker speculated in one of his documentaries that that the "giant gene" might be wiped out during the massive hunting. What is you're opinion about this? Saltwater crocodiles made an astonishing comeback in the past decades. Do you think the massive hunting would have forever affected their growth, or could they restore themselves (and their ability to grow) to the point they were let's say 100 years ago so we could yet again see more giant in the future?

Were other measurements taken? It would be nice to have at least dorsal skull length and a weight data for this specimen.

Is the relationship Skull length/body length what you could estimate from published regressions such as those of Webb & Messel (1978)? or is the skull of Lolong proportionally shorter, as it has been claimed to be the case for the largest crocodilians?

Those of us who work with very big fossil crocodilians would love to see more stuff published on this incredible crocodilian.

Yes, several other detailed measurements (mostly of the skull) were also taken. I will have a lot more to say about this next week. There are two reasons for this, first I need to double check everything carefully, and secondly I'm heading off to a remote island for the next week. I'll write this up properly while I'm there.

I will say though that his head length (snout to back of cranial platform) was 700 mm precisely. That's a head to body ratio of 1 to 8.8 which supports the trend of HL becoming proportionally shorter as size increases. The Webb / Messel regressions were derived with very few large croc datapoints, and break down for larger animals.

Vancatu, just quickly - hard to say his true age of course, 50 would be in the right ballpark though. Yes he is likely to grow further, although only by a small amount based on what we know of growth in large, older crocodilians. As for the size gene, I have another hypothesis. I'm going to think about it and write it up in the following week.

Wow! That's awesome Adam! It must have been a privilege measuring Lolong finally and getting a official size measurement! Well done! I can't wait to see more pics! I managed to find one on the ABC site of you measuring Lolong. If anyone is interested, here is the direct link to the image. Thanks.

"Vancatu, just quickly - hard to say his true age of course, 50 would be in the right ballpark though."

Would skeletochronology be helpful to answer this question? Of course we would need a study with a proper sample size for C. porosus, which will allow to estimate the number of growth lines lost in bone remodelling.

I think that "gigantism gene", in the case it would exist (and I don´t think this is so), would not dissapear so easy in a croc population under selective killing of the largest animals, just because crocs are able to reproduce before reaching maximum size. A giant croc might well have left lots of offspring before becoming a true giant. I guess this is more about self-regulation in croc populations.

Skeletochronology would give us a ballpark figure, yes. But that requires a section of long bone, which I doubt Lolong (or his keepers) want to give up just yet. Also, the technique isn't necessarily that accurate. It always underestimates age, but more importantly there has to be an annual variation in growth rate that's sufficiently large that you can see the change in bone density, which isn't always the case.

No, I don't like the giant size gene hypothesis. It's too convenient, and I don't think it makes much sense. I think giant size isn't dictated by a single factor, but a combination of conditions that in rare circumstances result in an exceptionally large crocodile. It's interesting to note that Lolong and other large crocs tend to be found in areas where their early years are spent in isolated areas away from human disturbance.

We've tried that once in the past, but like you said there are also accuracy issues. But the point is moot at this stage because, even though it's less invasive it still involves surgery and that's really not an option right now. I did raise the options while I was there, but there was no overriding feeling that it was worthwhile right now.

While looking over the Net regarding this story and cross-comparing the confirmed size to claims about other crocs, I ran across the Wiki entry for the notorious Gustave, who is supposedly about 20 feet by some visual estimates made against background objects known, etc.

Granted, Wikipedia is not the font of science all the time, and no one will know for certain about Gustave until he's either captured or shot dead. (Gustave is not particularly easy to approach, and both methods have failed in the past, someone supposedly popping him with high-powered rifle to little effect.)

Well, whatever the case with Gustave, in any event one citation from his Wiki entry happens to mention a supposed 23-foot Saltie "housed" in a park in India (Bhitarkanika Park on the Orissa coast).

http://www.underwatertimes.com/news.php?article_id=51790108324

Now, the lingo here was "housing", which I suppose can be read as enclosed after capture, or enclosed only in the sense that he's monitored on some semi-regular basis and can't really get around to attacking humans.

Or, perhaps this croc, named "Mahisasur", just does as he pleases and is really to be considered wild, and just hangs around the general vicinity.

Again to reiterate what I said about any Wiki entry, but I took note since supposedly Guinness made this "official", so I was curious if any real measurements would have been made, as one guesses from “official” outlets like Guinness.

The link is from 2006, and he could be deceased and so now Lolong gets the crown, or perhaps he's just actually to be considered a "wild" Saltie?

Actually, two supposed 23-footers have been mentioned as hailing from this area, and being of this size--a one "Baula Kumbhira" (The Crazy One), and the aforementioned fearsome man-eater "Mahisasur", or "Big Demon".

Or--more likely, and more relevant here--I'm guessing your opinion is that these magnificent lengths were not accurate?

Another story circulating in croc lore for other Indian Salties is one named Kalia, or "The Dark One" who was said to have been another notorious man-eater of over 23 feet or even more. He was killed by a local boat captain in 1929.

Others from this region were said to be even larger, with one specimen apparently killed in 1926 said to have exceeded even 25 feet, based on extrapolations made later from the skull measurements as a ratio of body size.

Wakefield, Guinness asked me about this crocodile before we originally declared Cassius to be the largest back in mid 2011. I rejected it at the time, as did Rom Whitaker, because it was based on an estimate and not actually measured (it's in a sanctuary under essentially wild conditions, and was observed during a survey and its length estimated). There was strong feeling that this estimate was very likely to be an exaggeration, but regardless without actual proof it could not be accepted as a record-holder. For this reason Guinness replaced it with Cassius. And now of course Cassius will be replaced by Lolong. At the very least this will encourage more accurate measurement of claimed largest crocodiles.

Incidentally I was always surprised that Guinness listed this crocodile back in 2006 anyway, as they're normally very careful about proof. Clearly they've since fixed this.

I also forgot to address Gustave. But obviously my answer is that Gustave has not been measured, and again there's no evidence that he is as large as claimed. Most large crocodiles (in fact, virtually every single one) end up being over-estimated by a fair degree. The Wikipedia article should be amended to make it clear that his size is an estimate. The National Geographic article it links to is wrong to state that he's 20 feet long (in fact it's clear further down that it's an estimate).

It seems that as with Gustave himself, some of the imagery of crocs takes on mythic proportions, and given the elusive and powerful nature of these two species of crocs, this is certainly understandable. Gustave for example is said to be playing "games" with people, to haunt people in their dreams, to taunt investigators, and to merely use humans as occasional target practice--killed but unconsumed--among other oddities in addition to sheer size.

Which, on that account, raises another question--why IS he so big compared to most all others of his species (whereas there are many large Salties) and stands alone in his size, however slightly overestimated.

Perhaps he really is clever, and for his part his elusive nature has allowed him to grow unabated while his comrades were killed off in the hunting and skin trade. It would be interesting to know just how many croclings he's sired (being a prime bull male and king of the river) that would in turn have his genetic traits.

(Vancatu mentioned "giant" genes, which as you mention are only a fraction of factors related to size with Salties, and one could guess this is probably the case with "Nile-ies", but still, one must wonder if any hatchlings of his could reach his potential if left alone, and the desperation, general poverty, or civil war strife in the region doesn’t reach the rivers for meat harvesting, easy cash, etc.)

I do remember now someone in the Nat Geo team a few years back estimated he's likely closer to about 6 meters, or about 18 feet.

When looking at Gustave's video, I can't help but think 20 feet would be a reasonable estimate.

Starting at 4.00 you see his true size.

http://www.youtube.com/watch?v=s6u0qYUfUwc

Considering that only an exceptionally large crocodile would actually scare a hippopotamus, and the video evidently shows that they are all scared of him, which is quite extraordinary.

I wouldn't be suprised if Gustave is about the size of Lolong, just as I wouldn't be suprised if he turns out as "only" 18 feet.

National Geographic launched a new documentary called "croc ganglands" which also shows a huge crocodile claimed to be 6 metres, which I doubt in this case. Very oftenly, 18 feet crocodiles are estimated as 6 metres. However, in the cases of Lolong, and Gustave, I believed their estimates were genuine from the start. And we now know Lolong's initial estimate as 20.1 feet was pretty darn accurate.

That's all reasonable. Still, there's an important difference between Lolong and Gustave's length estimates. The "estimate" you're referring to for Lolong was actually the first measurement taken in the field. It wasn't done correctly and so it wasn't completely accurate, but it was close. Gustave, on the other hand, has never been measured. The only evidence we have to go on is direct observations and film footage, both obviously prone to greater errors in judgment. Of course he's a very large crocodile, almost certainly between 17 and 21 feet. It's hard to compare them based on visual evidence: Nile crocs are heavier for their length than saltwater crocodiles, so that an 18 foot Nile crocodile (for example) typically looks bigger and longer than an 18 foot saltwater crocodile. Over-estimating size based on increased mass is a fairly common phenomenon with crocs.

Perhaps Gustave is 20 feet long, but unfortunately it's possible that we may never know. In comparison we have an accurate measurement for Lolong, and that's worth a lot.

I dont believe Lolong is anywhere near 20 ft. Gustave appear more impressive next to HIPPOS than what Lolong appear next to small philippine ppl. Where is the video of your measurment(with close up details) and who was the witness? Where is the independent verifications for Lolong's measurment? give me the names of the other ppl/organisation who has measured him.

Side, I was the independent verification for Lolong, as a crocodile specialist invited by National Geographic and the local Bunawan officials to collect accurate data on his dimensions for submission to Guinness World Records. Guinness don't need a long list of people to keep measuring him as long as the one who does the official measurement a) knows what they are doing and b) provides documentary evidence. Furthermore, the measurement was witnessed, filmed and photographed by National Geographic, local Bunawan officials, and the national media. The footage is the best evidence because obviously a close-up photograph can be set up. The reason the National Geographic video hasn't appeared yet is simply because they're making a documentary out of it and so any footage they shot (and own) won't be broadcast until the show premieres.

You also need to realise that I was highly skeptical of this myself when I first heard about it. Read the earlier entries in this very blog if you don't believe me. If you're aware of any of my writing on large crocs, you'll know that I need to see a tape measure on a crocodile preferably by someone who knows what they're doing before I'll believe it, especially given the number of exaggerated stories and misleading photographs that do the rounds. So accepting this isn't some magical turnaround or hidden agenda, but the result of hard facts.

And that's exactly why I don't place much weight in stories of Gustave's size. He may well be enormous, but the simple fact remains that he has not been measured. Until he is then any anecdotal reports and guesswork should be treated as such, and we have to defer to the actual data that now show Lolong to be the largest living crocodile in captivity.

NO, your not... this is your found, your scoop, your story! your way into famous and Guinness is your contact? (let me laugh a bit) i have seen plenty of videos and pics of Lolong and the only way for him to be 20 ft is if the philippine ppl next to him is 7ft tall (which they ofcourse is not) Common sense never lies, this croc is NO WAY NEAR 20ft. I dont know if you lies on purpose, or if you measured him wrong.

its when Guinness comes in i know its a scam, because Guinness are proven liars (see the dog "Giant George" for an example)

how was Lolong measured? did you just put the measuretape on him and following every curves on his body? or did you put the tape next to him and simply measured nose - tail?

Gustaves size isnt a story, its a FACT. Havent you seen the video where he is next to fullgrown hippos and is atleast as massive?I can promise you that Gustave would dwarf Lolong so badly that words couldnt do it justice. Also Gomek appeared much bigger than Lolong - and this is next to a "normal" tall man - not small philippines

Side, when you post as xismxist in YouTube comment threads, nobody can stop you making a fool of yourself. But this is my blog, and if you try the same juvenile ad hominem attacks and insults then I'm going to show you the door.

According to you, a classic example of the lesser Internet troll (Internet troglodytam minor), you think Philippino people are tiny, you can accurately judge dimensions based on low resolution YouTube videos, you think I don't know how to use a tape measure, you think that everyone who witnessed the measurement including myself are (in your words) liars, you think Guinness is a scam, you think Gustave is obviously bigger because you've seen videos of a large Nile crocodile in the same frame as a hippo, and you think based on this that he and Gomek (who was 17 feet 11 inches) would dwarf a crocodile that has been measured at 20 feet 3 inches? Did I miss anything?

Do you realise how ridiculous that all sounds? Do you realise how foolish you look? The only reason I'm allowing your message through at all is because we all need a good laugh. I see you just registered yesterday so you could bait me. Well congratulations, you made me waste 10 minutes writing this response which could have been better spent beating my head against the wall. If you want that to be your life's achievement, good for you. But if you want to rephrase your questions in a more mature manner I'm not going to hold a grudge and I'll address them.

I'm a pretty chilled guy, happy to take time out to help people with questions about crocs. But until you can be civil, grow up.

Well done Dr. Britton! stop the silly troll. We all hope to hear more on this amazing crocodilian soon.

What you told me about the shifting skull/body proportions in very large crocodilians is particularly interesting. It just made me reconsider all my prior size estimates of fossil crocodilians.

Moreno-Bernal, J. (2007). Size and Palaeoecology of Giant Miocene South American Crocodiles (Archosauria: Crocodylia). 67th Annual Meeting of the Society of Vertebrate Paleontology. Journal of Vertebrate Paleontology 27(supplement to number 3):120A

Hi Jorge, I'm just finishing off a paper about this which should be submitted soon. I'll try and make the PDF available. I'd be interested in reading the paper you cite as well, perhaps I can address how you did the estimations.

Hi Vancatu, I'll ask the production company if they have a ballpark date but I know it's still not quite finished. I'm not to going try and guess a date, I may be way off, but I'll certainly let everyone know when I find out. Hopefully it won't be too long, I'm keen to see it as well.

I've just seen a fairly recent documentary with Rom Whitaker, called Killer Crocs from the Monster Quest series of the History Channel. While this documentary is more about sensationalism than science, it shows a giant crocodile in Bhitarkanika National Park in India. I have little doubt this is the same one that was once recognised by Guinness as the world's largest. They were searching for this crocodile but I didn't expect that they would actually find and document it yet they did. They found him lying on a river bank and the crocodile didn't panic at all, which they usually do when confronted by humans, especially the more wary larger ones. Instead he just slowly went in the river, leaving behind a massive slide. He stayed on the surface while swimming away like a king and creating some big waves like it was a scene in Jaws. Those big crocs surely have big egos too. They're almost human beings. Anyway, Rom (who was impressed to say the least) and his companions went to the surface to measure the slide; it was 117 cm (46 inches) wide. Close by, a 10 feet crocodile had also left behind a slide which was only 52 cm. So I'm pretty sure this crocodile is of Lolong's size and I could understand why Guiness thought the same.

The documentary also shows scientists searching for, and finding, a giant American crocodile in the Florida Everglades. They estimated this crocodile at about 17 feet, making it the largest ever documented in the United States, which is impressive in its own right.

Anyway, in India Lolong has a serious contender. Maybe they should capture this croc to measure him as he's apparantly easy to find. But then again, they are sensative animals and we don't want him to get a heart attack, so maybe it's best to just leave him be. After all, we have Lolong to be excited about.

Hi Vancatu, as you can imagine I've discussed the Bhirtikanika croc with Rom but he does not believe that it's as long as previously claimed (23 feet). There was no justification for it to be listed by Guinness as there was no proof, no measurement.

I'll repeat my mantra though. Until a crocodile has been measured, we cannot claim to know its size.

It's important to note just what Lolong is. He's the longest living crocodile to have ever been accurately measured, where that measurement was properly documented and witnessed independently. He's also currently the longest living crocodile in captivity based on this evidence. It doesn't mean there could not be larger crocodiles out there still. I saw a photograph of another croc from Agusan Marsh which was clearly massive - this is the one they suspect may be bigger than Lolong. It's impossible to say from the photos, but it's possible. The Bhirtikanika croc may also be larger, who knows, and indeed I'd be shocked if there weren't other contenders out there hidden away that we don't know about yet. Maybe we'll never discover them before they die. It's nice to think such incredible creatures still exist though. You're right to describe them as having big egos. These are animals that have reached the top of their game, they've survived everything that's been thrown at them and they dominate. They deserve to have big egos. :)

I agree that the crocodile probably isn't 23 feet, which is a mythical size and I doubt crocodiles could reach such a size in the wild today.

When I saw him in the documentary being spotted he didn't immediately look like a record holder to me. He was seen from a distance and there wasn't anything to compare him with. But he left behind a very clear and fresh slide which was more than twice the size of the slide that was left behind by a 10 feet crocodile. Rom Whitaker was clearly impressed. Just as yourself he's a respected herpetologist with immense experience in the field. When I read your excitement about Lolong I was nearly certain he was genuine, and we now know he is.

But that said, I agree that as long as the crocodile isn't measured, it's nothing more than a big fish story. The same goes with Gustave.

What I'm even more interested in is Australia, which I consider the original home of the saltwater crocodile. I've another documentary of Rom Whitaker, called Supersize Crocs, which is one of my favorites. You will probably know this one as you're also part of it. Now I know you don't like to speculate much and I respect that. But when Rom visits you in Australia there are two crocs being named as reputed to be of a very large size. Could you shed some light on this? Also, you and Rom measure a large crocodile skull as being 68 cm. Does this one happen to be skull of the 6.2 m specimen that was caught in 1974? I have some doubts about the reliability of this record.

I have a huge respect for Rom, believe me. He probably inspired me more than anyone else to get into crocs in the first place. When Rom gets excited about a large croc I listen, he knows what he's talking about. I've since spoken with him about this, and Lolong, and I do not believe that Rom thinks the croc he saw in Bhirtikanika was the supposed record-breaker that Guinness had featured several years back. Rom sometimes reads this blog as well and I'll be sure to let you know if I'm misrepresenting him! I'd love to think this croc really was that large, how cool would that be?

The two crocs in Australia from Supersize Crocs are both represented by skulls. One is 68.8 cm and the other is 64.4 cm. Both were supposed to have come from crocs roughly 20 feet long. One of these (the 64.4 cm believe it or not) was apparently measured by government officials, although by the time they did it was in pieces and they had to measure bits separately. We know it was close to the apparent 6.2 m length although some inaccuracy was inevitable. This skull though is massive - very tall and broad, so it's a good clue that its length isn't necessarily the best indicator of its former owner's length. This is where it gets complicated.

You can never be 100% sure with any of this stuff. Stories change over time, get mixed up, records get lost, and what a pity there's no record of the crocodile's length for the 76 cm skull in the Paris Museum! But that's why it's so important to measure and record these big crocs properly for future reference.

So the 64.4 cm skull is from that alleged 6.2 m specimen? In Supersize Crocs, when Rom is in Africa, he measures the largest skull available at - if I remember correctly - 67 cm. It's then said that this skull would have come from a crocodile that was almost 20 feet in length. So wouldn't a 64.4 cm skull fall a little short to have come from a 6.2 m crocodile? You measured Lolong's head as 70 cm which couldn't fit more perfectly with his length. I could imagine how large the crocodile of the 76 cm skull would be. I think it's very plausible that this crocodile could have been as large as 22 feet, but that's mere speculation.

But I question the 1974 specimen. Who's to say that these government officials weren't acting in their own interest. A 6.2 meter crocodile would be a good boost for tourism in that region. Also, why aren't there any pictures available? They would have surely wanted to take some pictures of this giant, and photo cameras weren't a rarity anymore in 1974.

Yes, it was, but note what I said above that the skull was massive, much taller and broader than normal, certainly compared with the longer 68.8 cm specimen that's also here. There is some confusion over which of these skulls came from where, as both have remarkably similar stories (caught in fishing nets on Mary River, hacked to death by fishermen).

Lolong's head length to body length ratio is 1:9 - that's quite different to the roughly 1:7 - 1:7.4 that people tend to use for saltwater crocodiles, but of course the relative dimensions between head and body change with size (ontogeny) so this isn't surprising. The more data we get on these large crocs, the better an idea we'll have on what the patterns are, but it's certainly harder to predict total length from very large croc skulls.

I really hope the 1974 specimen is authentic, because it would prove that some giants survived the onslaught. But for now, the ones I personally consider genuine without any doubt are the Fly River one and Lolong, who are undisputedly 20 footers.

Yes, Guinness recently accepted the measurement as accurate, and have issued Bunawan with an official certificate. I haven't been informed of the timing of any press release nor the air date of the Nat Geo documentary, but it's likely the two will happen fairly closely together.

I just saw on Animal Planet on cable on the Lolong documentary about an 1 1/2 hrs ago. I was so fascinated on finding the biggest crocs and got to this blog from doing a google search. Anyway, Dr. Britton, how is Lolong doing and has he grown any bigger?

I just saw the Lolong documentary about 1 1/2 hrs ago on Animal Planet channel on cable. I was so fascinated to find out the biggest crocodile ever been documented with official measurement, and I happen to find this blog through google. Anyway, Dr. Britton, how is Lolong doing and has he grown any bigger from the last official measurement in November of last year? I'm not sure if my other post similar to this one was approved, so I'm writing another one. Thank you.

Thanks for the reply Dr. Britton. I just saw the rerun again on Animal Planet on cable, here in the United States. I was trying to see if you were in the footage, but I didn't call seeing you. I also saw the 2 people measuring Lolong, which I believe is probably shortly after they captured him. They were measuring him in the park where they put him for the public to see. It took 2 people to hold sticks attached to a single measuring tape with one end about a foot high above his head parallel to his nose, and the other end to his tail. I recalled they measured him about 20 feet and 3 inches. I believe the main person who helped captured Lolong, his name was Ronnie, and he stated he didn't sedate Lolong since that is dangerous to him and took a chance while he was awake. I was wondering what process did you take to accurately measured Lolong? Did you have to sedate him? Was he tied up? Were there a lot of people holding him down? Also will National Geographic have their own documentary, or is it the same episode I just saw 2 times on my cable?

I wasn't involved in the Animal Planet show, which was filmed after we visited. I know Ronnie well, and yes he coordinated the capture of Lolong. The measurement he quoted was indeed the one that we took - he knows exactly how long Lolong actually is.

Yes, I used sedatives on Lolong to measure him. The use of sedatives is quite safe if you know what you're doing, and I have years of experience using sedatives on crocodiles. Admittedly I had never sedated a crocodile as large as Lolong before so I was extremely cautious with the dose rate. But sedation was essential if had any hope of getting an accurate measurement, to straighten him out, run the tape measure down his back, and ensure the measurement was unbiased. We also used ropes and personnel to hold him down. We used two different methods to measure him, for comparative purposes. The official measurement is 6.17 m which converts to 20.24 ft or 20 ft 3 inches. So Ronnie would have quoted that measurement. Mayor Elorde now has the official certificate from Guinness with this measurement.

National Geographic filmed their own documented in November 2011, which is where you'll see the official measurement take place - that's the one I was involved in. This footage was used by Guinness to validate the measurement. There was a lot of work involved in the show which is why it has taken a while to appear, but it's scheduled to air in the fairly near future. I don't have a date I'm afraid, but I hope it's soon!

Found your blog while I was googling for any followup info on Lolong. Very informative stuff and I just want to thank you for putting the info out there where it can be found. I hope the NatGeo documentary is coming out soon, as it's more accessible to me than the Animal Planet documentary mentioned by others in the comments.

On a completely off tangent side note: how do you manage not to (pardon my french) sh*t in your pants when you're beside such awesome creatures?

when you look at pics and videos of lolong in profile (nose to tail) you will see that his skull / body ratio is just average 1:7 and no way near 1:9. 7 x 70 cm is 490 cm which is 16 ft - the length he appears to be. 20 ft is pure BS...

Ah, you're back! You're the guy who has been posting comments all over YouTube, under the username xismxist, claiming that I'm a liar and a fraud because you don't happen to believe the measurement I took was accurate, that it's some kind of global conspiracy by National Geographic, Guinness World Records and myself to get publicity and attention. As if any of us actually need to do that. And now you come back into the lion's den and post another comment on my blog saying that the measurement is pure BS because you've measured it yourself on some photograph. Who exactly are you hoping to convince? There's only so many ways I can say this, but you're wrong.

There's a peer-reviewed paper to be published next month in Herpetological Review (Vol 43, issue 4) which contains all the details of the measurements, including a great lateral photo of Lolong that very clearly shows his head length is nearly a 1:9 ratio against body length (the actual ratio is 1:8.8). This is very similar to the head length: body length ratios for other similarly large crocodiles, because the 1:7 head length ratio only really applies to juveniles. Whatever photograph you're using for your highly accurate and indisputable measurement is causing you great confusion.

I've also been told that Monster Croc Catch, the National Geographic show where the measurement was filmed, is finally going to air in the US in the near future. It's already started to appear on TV listings, keep an eye out for it because in there you'll very clearly see that the crocodile was measured properly. This may cause your head to explode, but stay calm - it's all going to be fine. You should be excited at the prospect of such a large crocodile, not arguing nonsense.

A paper next month in Herpetological Review? Oh my god! I have been waiting for it for a while. Please tell me there are implications for size estimates in giant fossil crocs... Do you also include data from other very big C. porosus?

Jorge, there are implications although it's primarily a paper about Lolong and factors leading to large size in crocodiles. There's some data from other large crocs, but there's another more analytical paper we're working on which might be more useful for size estimation. Trouble is data for very large crocs are rare so any analysis feels preliminary.

Dr BrittonHey, just to give some insight into the exaggeration of the length of crocs. From my own experiences living in Darwin, in Australia, as a twelve year old, i once chased a small saltwater crocodile down the beach(yeah, i know-that's so crazy and hard to believe)my dad and I estimated from our view of a few metres away, that the young croc was about a metre long at best.Then the local newspaper had on the front page of the sunday paper the next day that a two metre croc had been spotted down by the sailing club.

This confirmed to me that unless an accurate measurement can be obtained, the length of a croc cannot be specified and therefore cannot be proven to be of that length. Most people like to improve stories to attract more attention and a case of this may be Gustave in Burundi. Now that does not mean that Gustave may not be the largest crocodile of all time, but until he can be measured accurately,he can't officially be the biggest crocodile .

Photos can be misleading and deceptive as varied camera angles and use of space can make objects appear far larger or smaller than they actually are, that is yet another reason that measurement alone is the only method with which the accurate confirmation of a crocodiles length can be obtained.

Also, the head of a crocodile may give an indication of the potential size of a crocodile, but abnormalities form in the wild hence the presence for such large crocodiles in the wild today. the head to body ratio that was given for Lolong, 1:9, was bigger than the average 1:7, therefore re-enforcing my point that the size of the skull cannot make an individual crocodile larger than another by use of this technique and that the whole body must be measured to determine the precise length of a crocodile, therefore Lolong is the largest known crocodile to man.

Dear Dr Britton well done measuring Lolong we really enjoyed the programme which has just been repeated on Nat geographic - personally I do not think Side knows what he is talking about and ridiculing you via You Tube etc just shows what an uniformed person he really is. On the subject of Gustave he is a very big Nile crocodile judging by the hippos etc next to him but it is as you say he has never been measured whilst Lolong has been measured accurately - I must admit you have balls of steel standing so close to its head as it was coming round - Final question was there any further news on the reported larger crocodile in the Philippines My very best regards David P

Jorge, yes it is true unfortunately. They are conducting a necropsy this evening to determine the cause of death. I doubt they will be able to weigh the carcass as it needs to be dealt with rapidly before it deteriorates, and it won't really tell us anything. We already know the capture weight, and while he may have put some weight on (or lost some) it doesn't seem likely to be a significant amount. He was healthy until very recently.

Gustave is dead, he vanished likely he died of natural causes or was quietly poached these are the words of Patrice Faye who I contacted via social network Facebook i do believe it was Faye our conversation was in French.

The previous poster, Rob, seems to think that Gustave is dead based on an apparent conversation with the person who has been trying to catch him for years (Patrice Faye). That's the only source of information I've heard about it.

Do you believe this news to be true? http://www.indianexpress.com/news/private-museum-claim-to-have-worlds-largest-crocodile-skull/1081132/ , it is said that actually the largest crocodile skull is at one meter or three foot long. But I really doubt this news btw. What are your thoughts?

Do you believe this news to be true? http://www.indianexpress.com/news/private-museum-claim-to-have-worlds-largest-crocodile-skull/1081132/ , it is said that actually the largest modern crocodilian skull is at one meter or three foot long. But I really doubt this news btw. What are your thoughts?

Hi Dobba, let's just say that I'd need to see a photograph of that skull with a tape measure in the correct position before I believed that report. A 1 m long skull is possible if you're measuring the lower mandible length, which is frequently done for skulls. That would make it a large skull, but not necessarily the largest. The news report also neglects to mention the skull in the Paris Museum which is 76 cm DCL (dorso-cranial length), currently the largest verified C. porosus skull in the world. It also repeats the old chestnut about the Bhitarkanika record-breaking crocodile, but we know that this was a visual estimate made from a boat and never measured, and hence unreliable.

Thanks for the response Dr. Britton. Another question, according to Wikipedia crocodilian have somewhat triple-layered armour, first the tough scaly skin, then underneath the scaly skin are the osteoderms, next beneath its scaly sheath and craggy osteoderms is another layer of armor, built of rows of bony overlapping shingles, or osteoscutes, that are both strong and flexible. Is it true that crocodilian have triple-layered armour?

Hi Dobba, Wikipedia can be pretty good but it often contains nuggets of complete nonsense. There are no such things as "osteoscutes" in crocodiles. Only the osteoderms can really be described as being armour, as the skin itself provides protection but is easily breached by a strong tooth or claw. Also, the osteoderms are found within the dermal layer (beneath the epidermis) and not underneath the skin. I've tried correcting stuff on Wikipedia in the past, but someone usually uncorrects it pretty quickly.

That's impressive Vic Lin, but they have the total length estimate (for the original crocodile) wrong. The skull dimensions are provided, 39 inches long, which is 99 cm, which is a 1:9 ratio for a crocodile of 30 feet (9.1 m). But the 1:9 ratio is for DCL (dorso-cranial length), so tip of nose to back of cranial platform behind the eyes. A mandible length of 99 cm is certainly a large croc, very likely over 20 feet (6.1 m) long. Unfortunately it wasn't possible to get even a rough measurement of Lolong's mandible length (at the time I did it on the live croc) because he had so much muscle / fat around the back of the skull, but it was in that ballpark.

Would be nice to find out who bought the skull, and whether they own a tape measure. ;)

I have measured another large skull with an 85 cm mandible and DCL 66 cm so the ratio is near 1.29 as well. But it's not necessary because the one at auction has virtually the same mandible length with Paris Museum specimen so we can assume its DCL is also around 76cm range and has the same TL estimation.

At a ratio 1.29, Lolong's mandible length is about 90 cm. As far as I know its skull is still fridged in a local museum, but the fridge can be opened by tourists at will (!) Hope someone from that area can go there and measure it.

Hi Vic, which skull was the 66 cm DCL that you measured? Was it one from Bhirtikanika or Luzon? Thanks for bringing this new one to our attention, I sent the link to Rom Whitaker for his opinion about it, I'll let you know what he thinks. It would be indeed be great to get accurate standardized measurements from it, given its exceptional size, as there are so few really large skulls with such data. As for Lolong, last I heard they were going to prepare his skull, but by the sounds of it they still haven't done that.

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